Spica is a whirling double star | Brightest Stars | EarthSky Spica is a whirling double star By Deborah Byrd and Larry Sessions in Brightest Stars | April 23, 2016 Spica is a binary star, with two stars larger and hotter than the sun, telescopically indistinguishable from a single point of light. The star Spica is also called Alpha Virginis, because it is the brightest star in Virgo. Its color is distinctly blue-white, even to the eye. Photo by Fred Espenak. Read more about Spica at Fred Espenak’s website. Spica looks like one star, but it is at least two stars, both larger and hotter than our sun, orbiting only 18 million kilometers (11 million miles) apart. That’s in contrast to 150 million kilometers for Earth’s distance from our sun. Their mutual gravity distorts each star into an egg shape, with the pointed ends facing each other as they whirl around, completing a single orbit in only four days. Follow the links below to learn more about Spica, brightest star in the constellation Virgo the Maiden. Spica science.

Follow the arc to Arcturus, and speed on to Spica. Daniel McVey captured this image of the star Spica and the planet Mars on March 26, 2014. Spica is near Mars for much of 2014. How to see Spica. The best evening views of Spica come from spring to late summer when this star arcs across the southern sky. Spica rises in the east-southeast as the sunset glow fades in mid-April. At that time, it is visible most of the night. Two months later it beams at its highest point to the south in early evening. By the end of August, Spica can be viewed only briefly in the west-southwestern sky as darkness falls. Here’s how you can speed on to find Spica. First look for the Big Dipper in the northern sky. The Dipper is highest in the sky in spring and summer. Notice that the Big Dipper has a bowl and a long, curved handle. Find the Dipper, and then follow the curve of its handle outward, away from the Dipper itself.

The first bright star you come to is orange Arcturus , but if you continue past it in the curving path, the next bright star is Spica. Scouts and stargazers remember this trick with the saying: Follow the arc to Arcturus, and speed on to Spica. Virgo? Here’s your constellation Spica is the brightest light in the constellation Virgo the Maiden, and it is the 15th brightest star visible from anywhere on Earth. It’s virtually the same brightness as Antares in the constellation Scorpius, so sometimes Antares is listed as the 15th and Spica as the 16th brightest. No matter. Identify this beautiful blue-white star, and – with the Big Dipper’s help to spot it in the sky – it’ll be your friend for life. Classical illustration of the constellation Virgo the Maiden, via constellationsofwords.com. History and mythology of Spica. Spica is from the Latin word for “ear,” and the general connotation is that it refers to an “ear of wheat.” Indeed, the star and the constellation Virgo itself were sometimes associated with the Greek goddess of the harvest, Ceres.

There are many names and stories for Spica’s constellation – Virgo – in mythology, and by association with Spica as well. Fewer stories refer to Spica independently. Many classical references refer to Virgo’s stars as a goddess or with some association with wheat or the harvest. In Greece and Rome she typically was Astraea, the very personification of Justice; or Persephone, daughter of Ceres. In Egypt, Virgo was identified with Isis, and Spica was considered her lute bearer. In ancient China, Spica was a special star of spring known as the Horn. One Arabic name was Azimech, derived from words meaning Defenseless One or Solitary One. This title may be in reference to Spica’s solitary status with no other bright stars nearby. But Spica is not the most solitary star. That honor goes to Fomalhaut , sometimes called the Autumn Star. Artist’s concept of Spica from hypothetical planet. Image credit: Glyphweb.com Spica science. Spica is about 262 light-years away, based on data from the Hipparcos Space Astrometry Mission of the 1990s.

Spica is a binary star, with two stars which are telescopically indistinguishable from a single point of light. The dual nature of this star was revealed only by analysis of its light with a spectroscope, an instrument that splits light into its component colors. Both stars in the Spica binary system are larger and hotter than the sun, with the larger of the two, in fact, a blue giant or subgiant. The surface temperatures are estimated at 22,400 K and 18,500 K for the larger and smaller components, respectively. This compares to about 5,800 K for the sun. (“K” stands for “kelvins”, a degree on the absolute scale. At high values, each kelvin is about 5/9ths the corresponding Fahrenheit degree, so these two stars are about 40,000 F and 33,000 F, compared to 10,000 F for the sun.) Separated by just less than 18 million km (about 11 million miles), Spica’s two stars orbit a common center of gravity in only 4 days.

The resulting forces on these stars are so great that they are probably distorted, more egg-shaped than spherical. Although this cannot be visually seen, even through a telescope, slight magnitude variations may be evidence for such a distortion. The magnitude changes could be the result of the stars showing more or less surface area as they move through different orientations in their orbits. The light from these two stars taken together is, on average, more than 2200 times brighter than the sun. Their diameters are estimated to be 7.8 and 4 times the sun’s diameter. Spica is one of several bright stars that the moon can occult (eclipse). Based on observations of how the star’s light is extinguished when the moon passes in front, some astronomers think that it may not just be a spectroscopic binary star. Instead, they feel that there may be as many as 3 other stars in the system. This would make Spica not a single or even a double, but a quintuple star!

Spica’s position is RA: 13h 25m 12s, dec: -11° 09′ 41″ 10 Interesting Facts About Spica "The Blue Giant Star" | Astronomy Science 10 Interesting Facts About Spica "The Blue Giant Star" Print Email Astronomy Science ~ Spica (α Vir, α Virginis, Alpha Virginis) is the brightest star in the Virgo constellation, and the 15th brightest star visible at night. And following the star Spica 10 interesting facts: 1. Spica is 250 light years from Earth in the Virgo constellation. 2. Spica is a blue giant star and Beta Cephei type variable star. 3. This star is a double star (binary star system). The main star is classified as a giant star-type B1 III-IV. and the companion star is classified as a main sequence star with the type B2 V. 4. The Spica is a close binary star whose components orbit each other every four days. They were close enough that when viewed using a simple telescope, they are still seen as one star. Spica 5.

The main star Spica has a mass about 10 times the mass of the Sun and its radius reaches 7 times larger than the sun. While the companion star has a mass about 7 times the mass of the Sun and a radius about 3.6 times larger than the sun. 6. Brightness of the main star reached 12,100 times brighter than the Sun, while its companion star has a brightness of 1,500 times brighter than the sun. 7. Spica is one of the hottest stars are visible in the night sky. The main star Spica has a temperature of about 22,400 K while the companion star has a temperature of 18,500 Kelvin. 8. The main star is one of the closest star to the Sun. enough mass to explode into a supernova of type II. 9. Spica comes from the Latin word meaning "ears", and the connotations generally refers to the "ear of wheat." This is because the constellation of Virgo itself is sometimes associated with the Greek goddess of the harvest, Ceres. 10.

The other name of this star is Azimech, 角 宿 一, Spica Virginis, Alaraph, Dana, α Virginis, 67 Virginis, HR 5056, BD -10 ° 3672, HD 116 658, 18 144 GCTP, FK5 498, CCDM 13252-1109, SAO 157 923, 65 474 HIP. Virgo Constellation: Facts about the Virgin Virgo Constellation: Facts about the Virgin By Kim Ann Zimmermann | August 9, 2012 12:41pm ET MORE Virgo is a congested constellation with 26 known exoplanets — planets outside of the solar system — orbiting around 20 stars, and at least a dozen Messier objects. It is the largest constellation of the Zodiac and the second-largest constellation overall, behind Hydra. Well over a thousand galaxies are known members of the Virgo Cluster.

Credit: NASA/ Rogelio Bernal Andreo Locating Virgo Virgo covers 1,294 square degrees. Most of the constellation’s stars are dim, but Virgo's bright blue-white star, Spica, is fairly easy to locate. Stargazers can use the Big Dipper as a guide. Follow the curve of the handle down to the southeast until you come to the bright star Arcturus, in the Bootes constellation. Continue the arc to the next bright star, which is Spica. There's even a mnemonic phrase to help you remember: " Follow the arc to Arcturus, then speed on to Spica ." SKY MAP: The sky as seen at 10 pm local time on June 15 from midnorthern latitudes. Tied to fertility and agriculture, Virgo appears to stargazers in the Northern Hemisphere during the spring and summer months and to those in the Southern Hemisphere in autumn and winter. Right Ascension: 13 hours Visible between latitudes 80 and minus 80 degrees Best seen in May at 9 p.m. Spica , also known as Alpha Virginis, is the brightest star in the constellation.

Spica ranks as the 16th brightest star in the night sky and can be regarded as a nearly perfect example of a star of the first magnitude. It is a blue giant about 260 light-years from Earth. The star is about twice as big as the sun and its luminosity is 2,300 times that of the sun. It is known as the "ear of wheat" being held by Virgo. The second brightest star is Gamma Virginis, also known as Porrima and Arich, is a binary star. The third-brightest star, Epsilon Virginis, is a yellow giant that is also known as Vindemiatrix, or the Grape Gatherer. Zeta Virginis, or Heze, is a white dwarf notable for its exceptionally short rotation period of less than 0.5 days. The star 70 Virginis has one of the first known exoplanets, with one confirmed planet 7.5 times the mass of Jupiter. The Virgo Galaxy Cluster contains 11 deep space objects catalogued by Charles Messier , more than any constellation except Sagittarius, which has 15.

[Video: Galactic Eyes Peer Out Through Virgo ] Constellations ancient and modern grace the skies year round. Let's see what you know about the star patterns that appear overhead every night. Virgo – the constellation that signals the spring and fertility – Derek Shirlaw By Derek Shirlaw April 8, 2012 Science , Skygazing When it comes to constellations, only one other occupies a larger area of our field of vision in the sky than that of the virgin goddess, Virgo (and that’s Hydra – the water snake). Let’s take a closer look then at this fertile patch of our sky and unearth what it has to discover. Virgo is associated with the Greek goddess of Demeter, the corn goddess. The brightest star in the constellation is Spica (‘the ear of grain’) and this constellation is very much associated with spring and farming prosperity. In the image below, you can see the constellation take shape (click to embiggen and animate). The constellation of Virgo (animated).

Made using Stellarium Virgo lies along the ecliptic plane – the apparent daily path that the Sun, planets and their associated moons take across the sky – and was listed amongst 48 constellations by the Greek philospher Ptolemy in his book, The Almagest, published in the 2nd century and which forms the basis of the 88 modern constellations as we describe them. Spica (α Virginis – the ‘α’ denotes the ‘alpha’ or brightest star in a constellation) is often regarded as the first indication of spring as it appears prominantely to the East in the evening sky as we move into the season. This blue giant star is around 260 light years from Earth and is the 15th brightest in the night sky. It even makes an appearance on the flag of Brazil! The location of Spica on the flag of Brazil (animated). Spica lies above the white band across the globe on the Brazilian flag, and it symbolizes the part of Brazilian territory that lies in the northern hemisphere and the State of Pará (why not see if you can spot the other stars on the flag!?).

One way to remember how to find Spica is shown in the image below… use the handle of The Plough (or Big Dipper if you’re North American) to ‘arc’ around to Arcturus, and ‘spring’ on to Spica. How to find Spica using the Plough and Arcturus. Made using Stellarium Other cool things to find within the constellation are some other galaxies. Actually, the Virgo Cluster (as it’s known) contains some 1300+ galaxies, including Messier 87 (NGC 4486) and Messier 86 (NGC 4406). The brightest stars of Virgo and position of the Virgo Cluster. Made using Stellarium M87 is a giant elliptical galaxy (unlike our home – the spiral Milky Way galaxy) that lies some 53 million light-years from Earth and may be some 200 times as massive as the Milky Way making it the largest galazy in the Virgo Cluster.

At its centre is a super-massive black hole out of which streams an extraordinary flow of sub-atomic particles at nearly the speed of light as you can see in the colourised Hubble Space Telscope image below. Wow! Streaming out from the centre of the galaxy M87 like a cosmic searchlight is one of nature's most amazing phenomena, a black-hole-powered jet of electrons and other sub-atomic particles traveling at nearly the speed of light. In this Hubble telescope image, the blue jet contrasts with the yellow glow from the combined light of billions of unseen stars and the yellow, point-like clusters of stars that make up this galaxy. Lying at the centre of M87, the monstrous black hole has swallowed up matter equal to 2 billion times our Sun's mass. Image: NASA and The Hubble Heritage Team (STScI/AURA) M86 is racing towards us at 244 kilometers per second! Don’t panic (yet) though – it’s still some 52 million light-years distant from us. M86 is a lenticular galaxy – in-between an elliptical and spiral shape – and contains mostly aging stars and very little new star formation.

Messier object 86 by Hubble Space Telescope. Image: NASA / STSci If you’ve enjoyed this short insight to Virgo, why not check out some other constellations: Spring Triangle | Constellation Guide Constellation Guide Constellations: A Guide to the Night Sky Spring Triangle by admin The Spring Triangle is a prominent spring asterism formed by the bright stars Arcturus in Boötes constellation , Spica in Virgo , and Regulus in Leo . The asterism can be seen in the southeastern sky from March to May by observers in the northern hemisphere. It shares two stars – Arcturus and Spica – with the larger spring asterism known as the Great Diamond , or Diamond of Virgo. The Spring Triangle is easy to find using the stars of the Big Dipper . The line formed by the three stars of the Dipper’s handle leads first to Arcturus and then to Spica . Regulus , the third star of the triangle, can be found along a line extended from Megrez to Phecda, the two inner stars of the Dipper’s bowl. Spring Triangle.

Image: Wikisky Sometimes the Spring Triangle is taken to be the asterism formed by Arcturus , Spica and Denebola instead of Regulus , making a more nearly equilateral triangle. Denebola, which marks the Leo ‘s tail, is slightly dimmer than Regulus , but with a visual magnitude of 2.113, it is still an easy naked-eye star. Stars Arcturus , the brightest star in the constellation Boötes , is also the brightest star in the northern skies. With an apparent magnitude of -0.05, it is only dimmer than Sirius , Canopus and Alpha Centauri , the three brightest stars in the sky, located in the southern constellations Canis Major , Carina , and Centaurus respectively. Arcturus is in fact the third brightest individual star in the sky, slightly ahead of the brighter component in the Alpha Centauri system. Arcturus lies at a distance of only 36.7 light years from Earth and is one of the most luminous stars in the relative vicinity of the solar system.

It is an orange giant star with the stellar classification K0 III, a mass 1.08 times that of the Sun, and a radius 25.4 times solar. Spring Triangle location. Image: Wikimedia Commons/Tomruen Spica , the brightest star in Virgo constellation and the 15th brightest star in the sky, lies at a distance of 250 light years from Earth and has an apparent magnitude of 0.97. It is a spectroscopic binary star composed of two stars that are so close together that they are egg-shaped, making the system a rotating ellipsoidal variable. The primary component in the Spica system is a blue giant star classified as a Beta Cephei type variable, which means that it exhibits small variations as a result of pulsations of its surface. The two stars orbit each other every four days and cannot be resolved through a telescope. Regulus , the brightest star in Leo constellation , lies at a distance of 79 light years from Earth and is composed of two pairs of stars. Regulus A is a spectroscopic binary system composed of a blue-white main sequence star and a companion believed to be a white dwarf.

The two stars orbit each other about every 40 days. The Regulus system is the 21st brightest star in the sky, with a combined visual magnitude of +1.35. Spring Triangle stars. Image: Torsten Bronger. Deep sky objects The Spring Triangle contains a number of notable deep sky objects. Most of them belong to the Virgo Cluster, a large cluster of galaxies found between the stars Vindemiatrix in Virgo and Denebola in Leo . The cluster contains about 1,500 galaxies. The most prominent members include the bright galaxies Messier 49 , Messier 60 , Messier 84 , Messier 86 , Messier 87 ( Virgo A ), the Siamese Twins (NGC 4567 and NGC 4568), and the Eyes Galaxies (NGC 4435 and NGC 4438). Messier 49 is the brightest member of the cluster. It is more luminous than any galaxy closer to the solar system.

This deep image of the Virgo Cluster obtained by Chris Mihos and his colleagues using the Burrell Schmidt telescope shows the diffuse light between the galaxies belonging to the cluster. North is up, east to the left. The dark spots indicate where bright foreground stars were removed from the image. Messier 87 is the largest galaxy in the picture (lower left). Several notable galaxies lie in the region between Regulus and Denebola in Leo . These include the members of the Leo Triplet ( Messier 65 , Messier 66 and NGC 3628, also known as the Hamburger Galaxy ) and the M96 Group (Leo I Group), which consists of the galaxies Messier 95 , Messier 96 , Messier 105 , and at least nine other members. Leo Triplet of galaxies (Messier 65, Messier 66, Hamburger Galaxy).

Image: Wikimedia Commons/Hewholooks The Boötes Dwarf Galaxy , also known as Boötes I, can be found near Arcturus in Boötes and the globular cluster Messier 53 in Coma Berenices also lies close to the star, in the direction of Regulus . The galaxies Messier 85 and Messier 100 are found a bit further along the same line, also in the constellation Coma Berenices. Virgo the Virgin | Temple of the Earth and Stars Virgo the Virgin by Oraia Helene Continuing on our tour of the Zodiac, we are moving on to the sixth sign, Virgo the Virgin. The constellation of Virgo is best viewed in the month of May, shining between Leo and Libra. It is the second largest constellation in the sky, but because it doesn’t have a bright and easily identifiable pattern, I don’t think it’s very well known. Its name is simply the Latin word for “virgin,” and it is often pictured as a young woman carrying a sheaf of wheat. She is the only female figure represented in the constellations of the Zodiac.

Virgo’s brightest star is Spica (pronounced SPY-ka or SPEE-ka), which can be found by following the curve of the Big Dipper’s handle to the bright star Arcturus (arc-TOUR-uss) and then on to Spica, which lies along the same arc. Spica is a blue giant 260 light-years away, and is the 16th brightest star in the night sky. Its name derives from the Latin for “ear of grain.” (This is also the origin for the English word “spike,”when used in the context of a “spike of grain.”) Spica is also what’s called a variable star, meaning its brightness varies over a period of approximately four days. This is because Spica is actually a binary star, with the stars very close to one another – so close that the system ends up looking like it’s stretched out into an ellipse. As they move around one another, they cause changes to the amount of light that can be seen from earth, varying the star’s apparent magnitude. In the case of Spica, these changes are barely noticeable with the naked eye, but the star is the brightest of this type of variable star.

The Virgo Cluster of galaxies makes the constellation particularly interesting to astronomers, and contains something like 2000 galaxies. That’s whole galaxies, full of stars. There’s also another very cool galaxy that isn’t part of the Virgo Cluster, but lies about 10 degrees west of Spica near the lesser-known constellation of Corvus the Crow. It’s called the Sombrero Galaxy – guess what it looks like? So here might be a good time to point out a little matter of scale and distance. The stars in every constellation we see are members of our own galaxy, the Milky Way. We see them as separate and distinct because a) they are relatively close to us, and b) our solar system sits on the outer edge of our galaxy, making our sky much darker than if we were situated near the center. When we see the long river of stars crossing our sky that gave the Milky Way its name, we’re looking toward that center, and individual stars all sort of run together.

Then when we look further out, at other galaxies separate from ours, we don’t see individual stars at all with the naked eye, just an indistinct blur It’s like seeing a big crowd of people from a distance – you know it’s a group of people, but you can’t separate one from another until you get closer. So when we say that a constellation “contains” a galaxy or group of galaxies, that’s a little bit misleading because, again, the constellation itself consists of stars in our galaxy, while the other galaxies are, well, other galaxies. But they appear to lie within the outlines of a given constellation – the appearance of which, after all, is itself based on our perspective here on earth. So the galaxies and other deep-sky objects aren’t considered part of the constellation – you wouldn’t see them connected up with the rest of the stars in a diagram depicting Virgo, for example – but they are visible in the region of space assigned to the constellation. That’s what it means to say that a constellation “contains” or “includes” things like galaxies, nebulae, star clusters, etc. Anyway.

In mythology, the constellation of Virgo has been associated with most of the major female deities of the ancient world, especially mother Goddesses and Goddesses of fertility and agriculture. (Recall that she’s usually pictured carrying a sheaf of wheat.) These Goddesses include Ishtar of the Babylonians, Isis of the Egyptians, Demeter and Persephone in Greek myth, as well as the Virgin Mary in the Christian tradition. She was also associated with Astraea, a Roman Goddess of justice, in which guise she was pictured carrying the scales of the constellation Libra, which sits close by. Astrologically, Virgo is the sign of mutable earth, and is associated with the sixth house, which typically has to do with one’s relation to work and service, and also to sickness and health. Traditionally speaking, the sign is ruled by Mercury, though some modern astrologers give rulership to the asteroid Ceres (and sometimes to the four major asteroids as a group). Mercury does seem something of a bad fit, but I don’t really work with the asteroids myself so I don’t have a strong opinion about them.

Ceres, of course, is named for one of the grain Goddesses associated with the constellation of Virgo, so I can understand the attraction of changing the rulership. Generally speaking, the energy of Virgo represents a significant shift from the energy of Leo before it. (As it happens, this is another sign I have a particular interest in, because most of the traits I have that don’t seem to fit my Leo sun come from my Virgo moon. And they are two of the most dissimilar signs to appear next to each other in the Zodiac.) Unlike Leo, there is much less emphasis on asserting individuality and self-sufficiency in Virgo. Instead, the emphasis shifts toward total efficiency and effectiveness. Instead of Leo’s craving for social recognition and praise for a job well done, the Virgo personality focuses more on simply doing the job well. At the same time, the Virgo personality can be a little more timid and cautious when encountering the world than the enthusiastically outgoing Leo. At its best it represents a more chastened maturity in the development of the self, though at its worst it can be fearful and conformist in social situations. Virgo thrives on order and mastery, with a tendency to strive for perfection.

The Virgo personality is often ruthless in its self-criticism (and sometimes similarly harsh in judging others.) Whether because of this or despite it, Virgos often excel at writing and various physical crafts. As an earth sign, Virgo is eminently practical and serious, and as a mutable sign, Virgo is looking to change things – so while Virgos may not enjoy being in positions of high visibility in the world, effectiveness in promoting change is very important to them. The Virgo needs to feel effective, though that doesn’t necessarily mean they need to be in charge. There is also a strong desire for order and predictability, and Virgo is often something of a control freak. Things going wrong despite the best of plans will tend to bother Virgos more than most other signs. And sometimes the inability to achieve perfect order or live up to her very high standards will cause a Virgo to give up on them completely. So let’s take a look at this sign in the position of a Sun Sign, a Moon Sign, and a Rising Sign. As a Sun sign, Virgo is full of activity. Virgos like to keep themselves very busy, and often have difficulty taking time off to do nothing.

They will often approach their work in a very analytical way, and are excellent at focusing on small details. Virgos have a strong sense of duty, and can easily find themselves imposed upon and taken advantage of because of this. (I can tell you from experience that this goes for Virgo Moons also.) It can also lead to an excess of nervous energy which can lead to tension and worry. At the same time, Virgos are generally very practical, and their approach to problems is generally to get down to the practical and analytical business of solving them. Virgos like to have many hobbies with which to fill their time, and are often very good at craft work and gardening. Their tendency toward criticism (and self-criticism) can cause tension in family relationships, but they are also very attentive and eager to provide for their loved ones. As a Moon sign, Virgo speeds up one’s initial reactions to situations, which will tend to be practical, helpful, and logical. A person with Virgo moon will want to investigate and double-check information before accepting it as true.

This tendency also applies to the person’s own internal thoughts and feelings, which can serve to clarify thoughts and rein in knee-jerk emotional reactions, though it can also lead to the emotions becoming over-rationalized, and somewhat mistrusted. Overall this placement tends to result in a sensible and reliable person, eager to help but also critical of those unwilling to help themselves. As a Rising sign, Virgo brings a lot of practicality and careful deliberation to the personality. With Mercury as the planet of rulership (or A planet of rulership, if you prefer to also include Ceres), the need for communication may come to the fore, though there will often be some shyness at first. As usual with the Rising Sign, the opposite sign (in this case Pisces) will often come into play with regard to long-term relationships, bringing a kindness and tenderness of emotion that can make the relationship very special. Spica - Alpha Virginis | Constellation Guide Constellation Guide Constellations: A Guide to the Night Sky Spica by admin Spica, Alpha Virginis, is the brightest star in the southern constellation Virgo and the 16th brightest star in the sky.

It is a blue subgiant star located at a distance of 262 light years from Earth. Spica is really a close binary star system. It is one of the nearest massive binary stars to the solar system. The name Spica (pronounced /ˈspaɪkə/) comes from the Latin phrase spīca virginis, meaning “Virgo’s ear of grain.” The Latin word spicum refers to the ear of wheat Virgo holds in her left hand. In Greek and Roman mythology, the constellation and the star were associated with Demeter (Ceres), the goddess of the harvest. Spica is bright both because of its size and relative proximity to Earth. The components in the system have a radius 7.40 and 3.64 times that of the Sun. Both stars are significantly brighter than the Sun, with total luminosities (including ultraviolet radiation) of 12,100 and 1,500 times solar. Spica A and Spica B both belong to the spectral class B, which makes them bluish-white in colour.

The stars are also much hotter than the Sun, with estimated surface temperatures of 22,400 K and 18,500 K, compared to the Sun’s 5,800 K. This makes Spica one of the hottest first magnitude stars. Virgo constellation. Image: Till Credner The primary star in the system is halfway between a subgiant and giant on the evolutionary scale. It belongs to the spectral class B1 III-IV. With a mass more than 10 times that of the Sun, Spica A is one of the nearest stars to Earth that are massive enough to end their life in a Type II supernova explosion. The primary component is responsible for about 80 percent of the light that comes from the star system. Spica is classified as a Beta Cephei variable. It exhibits variations in brightness over a 0.1738-day period. The star is a very fast spinner, with a projected rotational velocity of 199 km/s at the equator.

The two components in the Spica star system are so close together – only 0.12 astronomical units apart – that they complete an orbit around each other every four days, and can’t be resolved in a telescope. The star’s binary nature wasn’t discovered until its light was analyzed with a spectroscope. The stars in the Spica system orbit a common centre of mass (barycentre) at about 56 miles per second at a distance of only 18 million kilometres, or 11 million miles, compared to 150 million kilometres for Earth’s distance to the Sun. As a result of their proximity, the gravity distorts both stars into an egg-like shape, with their pointed ends facing each other. The stars’ shapes can’t be seen directly, not even in a telescope, but slight changes in magnitude may be evidence that they are distorted by the interaction. Spica in Virgo constellation. Image: Torsten Bronger. The system is classified as a double-lined spectroscopic binary, showing a Doppler shift in the absorption lines of the stars’ spectra resulting from the changes in the star system’s orbital motion.

The variations in Spica’s magnitude are likely the result of the two stars showing more or less surface area as they orbit each other. The stars have different orientations during different phases of their orbits and, as they are distorted in shape, their apparent diameter changes over the course of an orbit. Spica is a rotating ellipsoidal variable, which means that the two stars in the system are distorted by their gravitational interaction. The system is a non-eclipsing binary, with neither star passing in front of the other from our point of view. Spica exhibits variations in magnitude of 0.03 over a period matching the stars’ orbital period. Spica B, the secondary member of the star system, belongs to the spectral class B2 V, which means that it is still on the main sequence. It is smaller and less massive than the main component, with only 7 solar masses. The secondary component provides a rare example of the Struve-Sahade effect, which means that the star’s spectral lines exhibit an anomalous change in strength over the course of an orbit, and become weaker as the star moves away from the observer.

This may be the result of a strong stellar wind from Spica A scattering the light from the smaller star as the latter recedes. The Alpha Virginis star system is a massive source of X-rays. At least some of the X-rays are believed to be produced by violent collisions of the stars’ stellar winds. Diagram showing how to locate the star Spica using Arcturus as a guide. Drawn by Jim Thomas on 19 June, 2006. Spica can be located by following the arc of the Big Dipper ‘s handle. The first bright star along the imaginary line is Arcturus , the Bear Watcher, and following the same curving path, the second bright star that appears is Spica. The apparent distance from Arcturus to Spica is roughly equal to the distance between Arcturus and Alkaid, the star marking the tip of the Dipper’s handle. The best time of year to observe Spica is from spring to late summer. The star emerges on the horizon in the east-southeast at sunset in mid-April and can be seen throughout the night. Spica can be found at its highest point to the south in the early evening about two months later.

By late August, it can only be seen for a short period after sunset in the west-southwestern sky. The Sun passes about 2 degrees north of the star every year around October 16. Spica’s heliacal rising occurs about two weeks after this date. Venus passes near the star every eight years around the same date. Spica lies close to the ecliptic, roughly 10 degrees south of the celestial equator, and can be occulted by the Moon, sometimes even by planets. The last time it was occulted by a planet was on November 10, 1783, when Venus passed in front of it. The next planetary occultation, also by Venus, will occur on September 2197. Based on observations during lunar occultations, when the star’s light is occulted by the Moon, some astronomers believe that there may be up to three more stars in the Spica system. FACTS Together with the bright stars Arcturus in Boötes constellation , Denebola in Leo , and Cor Caroli in the constellation Canes Venatici , Spica forms an asterism known as the Diamond of Virgo , 50 degrees in extent.

Great Diamond of Virgo. Image: Friendlystar at wikipedia.org Along with Regulus in Leo , Alpha Virginis is believed to be one of the bright stars that made it possible for Hipparchus (160 – 120 BC) to discover the precession of the equinoxes, after comparing his data to that of the Alexandrian Timochares, who had observed Spica and Regulus around 300 BC. Spica was later observed by Nicolaus Copernicus, who also used it to study precession. Spica’s projected galactic orbit takes the star between 22,500 and 24,400 light years from the centre of the Milky Way. The star moves through the galaxy at a speed of 18.9 km/s relative to the Sun. A temple to Menat at Thebes, constructed around 3200 BC, was oriented toward Spica. As a result of precession, the star’s position relative to the temple slowly changed over time.

A number of temples were oriented to Spica’s setting, including the temple of the Sun at Tell el-Amarna (2000 BC), two temples at Rhamnus in Greece (1092 and 747 BC), another two at Tegea, Hera’s temples at Olympia (1445 BC), Girgenti and Argos, the temple of Diana of the Ephesians (715 BC), and the temple of Nike Apteros at Athens (1130 BC). The temple orientation indicates that these cultures had knowledge of the precession of the equinoxes far earlier than Hipparchus documented his discovery. This beautiful new image, taken during a time lapse set at the Atacama Large Millimeter/submillimeter Array (ALMA) is another dramatic Ultra High Definition photograph from the ESO Ultra HD Expedition. ALMA, located at 5000 metres above sea level on the remote and empty Chajnantor Plateau in the Chilean Andes, marks the second destination for the four ESO Photo Ambassadors on their 17-day trip.

The ambassadors are equipped with state-of-the-art Ultra HD tools to help them capture the true majesty of sights like the one pictured here. Some of the 66 high-precision antennas that comprise ALMA are visible here, with dishes pointed aloft, studying the cold clouds in interstellar space, and peering deep into the past at our mysterious cosmic origins. The spectacular javelin of light over the ALMA array is a shooting star, slicing through the image in a vivid streak of colours. Emerald green, golden and faint crimson hues blaze brightly as the meteor burns up as it enters the Earth’s atmosphere and makes its fiery voyage across the sky. As the high-speed fireball — which is, in reality, a small grain of rock from interplanetary space — interacts with the atmosphere it heats up, vapourising the surface layers of the meteor, which are left behind in a glowing trail. These trails disappear in just a few seconds, but are captured here at the click of a button. The brightest star in the constellation of Virgo (The Virgin), known as Spica, and our neighbouring planet Mars glow brightly in the centre of the image — cosmic spectators to this fiery descent as they rise above the horizon. Image: ESO/C.

Malin In ancient Greece, Spica and Virgo constellation were associated with Demeter, and also with Dike, the goddess of justice, and Persephone, wife of Hades and daughter of Demeter. Spica has been known by many different names across the cultures. The 17th century German astronomer Johann Bayer called the star Arista. In medieval times, the names for the star included Azimech and Alarph. Both were derived from Arabic; Azimech from al-simāk al-a‘zal, meaning “the undefended” or “the solitary one,” and Alarph, from the Arabic phrase meaning “the grape gatherer.” Spica’s other names included Sumbalet, meaning “the corn ear,” which is the Arabic name for the constellation Virgo , and also Sombalet, Shibbōleth, Sombalet, and Sembalet Eleandri. Babylonian observers called the star Sa-Sha-Shirū, meaning “the virgin’s girdle.” The star represented the wife of Bel. In China, Spica is known as Jiao Xiu 1 and belongs to the constellation Jiao Xiu.

Ancient Chinese considered Spica to be a special star of spring and called it Kio, the Horn. Spica also marks the eye of the Dragon as it belongs to the first Chinese lunar mansion, which is the first sector for the Azure Dragon or the Dragon of the East, the guardian god of the eastern direction in their astrology. The major part of the dragon’s figure was formed by Scorpius constellation , with the bright Antares , known as the Fire Star, marking the dragon’s heart. Egyptians identified Virgo with the goddess Isis, and saw the star Spica as Isis’ lute bearer. They also knew the star by a different name, Repā, meaning “the lord.” To Hindu observers, the star corresponds to the Nakshatra Chitra. They called the star Citrā, meaning “bright.” Spica represents the Brazilian state of Pará on the Brazilian flag.

Spica – Alpha Virginis Coordinates: 13h 25m 11.5793s (right ascension), -11°09’40.759” (declination) Spectral class: B1 III-IV/B2 V Distance: 262 light years (80 parsecs) Apparent magnitude: 1.04 Absolute magnitude: -3.55 (-3.5, -1.5) Orbital period: 4.0145898 days Mass: 10.25 solar masses (Spica A), 6.97 (Spica B) Radius: 7.40 solar radii (Spica A), 3.64 (Spica B) Luminosity: 12,100 solar luminosities (Spica A), 1,500 (Spica B) Temperature: 22,400 K (Spica A), 18,500 (Spica B) Rotational velocity: 199 km/s (Spica A), 87 km/s (Spica B) Variable type: Beta Cephei

, rotating ellipsoid Pronunciation: /ˈspaɪkə/ Designation: Spica, Alpha Virginis, α Virginis, 67 Virginis, Spica Virginis, HD 116658, HR 5056, SAO 157923, BD -10°3672, GCTP18144, HIP 65474, FK5 498, CCDM 13252-1109

Question: The blue giant star, Spica, lies in which constellation?
Answer: Virgo